单个催化剂粒子内的温度和催化激活的时空异质性
Yu Tian1,2, Mingbin Gao1, Hua Xie1
1National Engineering Research Center of Lower-Carbon Catalysis Technology, Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, People's Republic of China.
Journal of the American Chemical Society
|February 9, 2024
概括
精确测量工业催化剂粒子内部的温度是一项挑战. 这项研究引入了一种新的成像技术来绘制温度分布图,揭示它们在化学反应中的关键作用.
科学领域:
- 化学工程
- 材料科学
- 光谱学
背景情况:
- 温度对化学转换,反应动力学和热力学有重要影响.
- 在工业催化剂颗粒 (微米到毫米) 中直接测量温度是一个重大挑战.
- 了解催化剂内部温度对于优化催化剂设计和反应动态至关重要.
研究的目的:
- 开发和展示一个空间时间分辨率测量方法在单独的催化剂颗粒.
- 在甲醇与碳化合物反应过程中研究催化剂特性对内部温度分布的影响.
主要方法:
- 使用微流体芯片制造含有化物和功能纳米温度计的催化剂颗粒.
- 采用双光子共焦显微镜和上转变光 (UL) 成像技术.
- 在反应过程中测量催化剂颗粒内的温度分布.
主要成果:
- 在催化剂颗粒内部成功地进行了时空解析的温度映射.
- 显示热带石的密度和颗粒大小显著改变了内部温度分布.
- 观察到温度异质性对反应中间体的激活和活性部位的利用具有重要影响.
结论:
- 拟议的成像方法可以准确地测量催化剂颗粒中的温度.
- 内部温度异质性是催化性能和反应机制的一个关键因素.
- 这项研究为研究工业催化剂的反应机制和动力学提供了新的途径.
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